r-tree-diagram
Description
A function to create tree diagram visualizations for conditional probabilities in R.
Input data
The only required input to the function is a dataframe with the following structure. The pathString column should have the names of the potential outcomes at each tree level. For example, there will be no rain or there will be rain as our first-level outcome. The column also includes second-level outcomes (e.g., no rain and a 65 degree day) separated by a forward-slash /. The prob column contains the probabilities associated with each path. Although there is no limit to the number of conditional paths that might be included, at a certain stage the visualization will become challenging to read.
| pathString | prob |
|---|---|
| no rain | 0.72 |
| no rain/95°F | 0.25 |
| no rain/85°F | 0.55 |
| no rain/75°F | 0.15 |
| no rain/65°F | 0.05 |
| rain | 0.28 |
| rain/95°F | 0.05 |
| rain/85°F | 0.25 |
| rain/75°F | 0.35 |
| rain/65°F | 0.35 |
Usage
make_my_tree(mydf = prob_data, branch_levels = NULL, show_rank = TRUE, direction = “LR”, root_name = “Start”, font_name = ‘helvetica’)
Arguments
| Argument | Description |
|---|---|
| mydf | dataframe with the probability data as described above |
| branch_levels | the number of branch levels to show |
| show_rank | logical. should ranks be shown in final branch |
| direction | the direction of the tree. One of “LR” (left-to-right), “RL” (right-to-left), or “TB” (top-to-bottom), or “BT” (bottom-to-top) |
| root_name | character. the name label for the starting node |
| font_name | character. font type such as ‘helvetica’ (default) or ‘times’ |
Required libraries
library(tidyverse)library(data.tree)
Examples
Default output that shows everything
make_my_tree(prob_data)
Remove the rank display variable
make_my_tree(prob_data, show_rank = FALSE)